The UK is in lockdown because of fears the National Health Service would become “overwhelmed” within weeks if measures weren’t brought in.
Pressure on the NHS is always difficult in winter because people are more likely to have accidents or get ill at this time of year.
But Covid-19 is making the situation much tougher.
It’s a situation that health services around the world are facing and why governments are taking extra steps to stop the situation arising.
BBC health correspondent Laura Foster explains what an overwhelmed health service would be like and how it can be avoided.
Video by Laura Foster, Terry Saunders and Kate Forbes